Friday, September 24, 2010

Bird Mortality in the Alberta Oilsands

On Tuesday September 7th 2010 the Toronto Star published an article with the title: “Birds dying in oilsands at 30 times the rate reported, says study” by Bob Weber. An alarming headline like this is sure to draw attention, especially when it claims that the information is drawn directly from a reliable source such as a study. The article is based on research done by Kevin P. Timoney and Robert A. Ronconi titled: Annual bird Mortality in the Bitumen Tailings Ponds in North-Eastern Alberta, Canada. It was published in the The Wilson Journal of Ornithology. A question to consider is how much of the original study information is transmitted to readers of the article on the Toronto Star’s website. What other information has been added? Has any information been misrepresented?

To answer these questions one can compare the points emphasized by Weber with the information stated in the original paper. Weber highlights the discrepancy between the statistics that the researchers arrived at compared to the previously accepted mortality data collected by employees of the bitumen industry. This emphasis is present in the discussion section of Timoney and Ronconi’s paper. Weber directly quotes them, writing:

“Industry-reported data on bird deaths are problematic as they are not systematic, repeatable and statistically robust.” (Weber, 2010)

These statements leave the readers of the secondary article with an understanding of the scientists’ opinions on the subject, similar to what they would have learned from reading the primary article.

Weber does a very good job of conveying how the raw data used in the study was obtained. He mentions that the sources of the raw data are a variety of oil company reports, Government of Alberta data, and independent studies from the 1980’s. Although it is not mentioned in the primary article, Weber reports that Timoney said, “Those surveys [from the 1980’s] remain relevant because methods of deterring bird landing haven’t changed much since then...” (Weber, 2010)

This information gives the reader of the secondary source a reasonably good idea of what the researchers aimed to do, and even displays some of the logic they used when making decisions about experimental design. That said, it is difficult to evaluate this statement because it cannot be found in the primary article, and appears to be a quote from an interview.

Weber provides his readers with a basic, but accurate explanation of the calculations involved in processing the raw data to obtain the estimate of bird mortality. He writes,

“Using averages for the mortality rate of oiled birds, and adjusting for the increased size of tailings ponds over the last two decades, Timoney came up with what he says is a more reasonable estimate for bird deaths in the 120 square kilometres of ponds he studied.” (Weber, 2010)

The results of this study were presented in the secondary article as follows: “The 14-year median, including raptors, songbirds, shorebirds and gulls, is 1,973 deaths every year.” (Weber, 2010) A casual reader would most likely accept this number because the article is based on a scientific study. Weber points out that the study was funded by Dalhousie University, a credible institution. Interestingly enough, the number 1,973 was not mentioned in the primary source. It may have been mentioned in an interview with the researchers, but according to the primary document:

“An estimate based on the lowest observed mortality at Syncrude’s Mildred Lake Settling Basin (MLSB) of 7.2 birds/km2 in 1985 yielded an annual mortality of 863 birds. A medium estimate based on Syncrude’s MLSB (1980–1985) average mortality of 13.38 birds/km2 yielded an annual mortality of 1,614 birds. A high estimate based on the weighted mean mortality rate for all years at Syncrude’s MLSB and Suncor’s Tar Island Ponds 1 and 1A of 41.7 birds/km2 yielded an annual mortality of 5,029 birds.” (Timoney & Ronconi, 2010)

It becomes noticeable that Weber failed to mention this wide range of results obtained by modelling the situation. Although the number 1,973 given by Weber falls into the range of the results described in the above quote, readers might want to consider where this number came from if it was not taken from the primary article.

Weber makes another claim that is not supported by the content of the primary source, stating that, “The total mortality is unlikely to have much overall impact on the millions of birds from dozens of species that migrate through the Athabasca watershed, one of the continent’s main flyways.” (Weber, 2010)

Conversely, Timoney and Ronconi state that, “Tailings ponds exceed the extent of natural water bodies in the area, continue to increase in extent, and lie along an internationally significant flyway; thus, they may pose a significant regional mortality risk.” (Timoney & Ronconi, 2010)

The researchers use words that express uncertainty such as ‘may’ or ‘might’, but the phrase ‘it is unlikely’ creates a tone of more certainty in Weber’s article. This tone could be misleading.

Timoney and Ronconi emphasize that their study has many limitations because of the difficulties associated with accurately recording bird mortality. Weber also makes a point of some limitations of the study. He writes that, “His [Timoney & Ronconi’s] study...didn’t account for birds that landed and were oiled at night or that simply sank under the surface of the ponds.”

There were other limitations to the study that Weber did not discuss, including assumptions made by the researchers about mortality rates of birds that do come in contact with oil, about birds’ usage of land being uniform throughout the geographic area of the study, and that no observations on bird mortality were made between the months of November and April. (Timoney & Ronconi, 2010)

Although Weber left out this information, by providing some of the main limitations of the study in a relatively short newspaper article, he prompts readers to think about the limitations, rather than accept that this information is undoubtedly accurate.

Finally, the extra information in Weber’s article is beneficial to his readers because it allows them to look at the implications of this study in a broader way. He gets another perspective on the matter by interviewing Alberta Sustainable Resource Development Minister Mel Knight who assures readers with the news that,

“I would not argue at all with the study with respect to the fact that there could be better work done on monitoring, and we’re going to work to do that.” (Weber, 2010)

This type of information is good for the public to know, even though it does not appear in the primary article.

Overall, the primary and secondary articles convey the same idea, with the exception of a couple of comments made by Weber that are not justified in the primary article. Therefore, in order to fully understand the shocking newspaper headline, one should read further into the topic and get the details that the author of the newspaper article may have omitted.